Valve mechanism



Marsh 24, 1942.A P. c. TEMPI-.E

vVALVE MECHANISM,

Filed April 21. 1959 PA UL C. TEMPLE Patented Mar. 2.4, A1- 942 VALVE M'ECHAN ISM Paul C. Temple, Decatur, 111.,.assignor to A. W. Cash Company, Decatur, Ill., a corporation of Delaware Application April 21, 1939, seria1N0.269,143

` 4 claims. (ci. 137-68) This invention relates to valve mechanisms, and more particularly to valve mechanisms of the type adapted to control the ow of fluid in accordance with pressure variations as well as changes in liquid level.

In certain apparatus for the manufacture of ice it has been proposed to employ a series of vessels forming heat exchangers arranged to effect a transfer of heat from water, through intervening metal walls, to a suitable refrigerant in liquid form. As soon as the water has been frozen in one vessel, refrigerant in gaseous form is introduced at a higher pressure to force the liquid refrigerant out of the vessel and into the next vessel in the series. Thevsuccessive vessels are connected by conduits provided with valves, and these valves must be opened at theproper time to allow transfer of the liquid and closed promptly when the transfer has been eected. So far as I am aware, no valve mechanism suitable for this purpose has been disclosed heretofore.

It is accordingly one object of the invention to combine into one heat exchanger a simple, inexpensive and reliable valve mechanism particularly suitable for controlling the flow of liquid refrigerant therefrom to another heat exchanger.

It is a further object of the invention vto combine with a heat exchanger for liquid refrigerant a valve mechanism arranged to open automatically upon a predetermined increase in pressure, and to close automatically upon a predetermined reduction in liquid level irrespective of such pressure increase.

It is a further object of the invention to combine wlth a heat exchanger for liquid refrigerant a valve mechanism particularly adapted to control the discharge of liquid therefrom, this mechanism being so constructed and arranged as to permit such discharge of liquid when the pressure thereof is increased suiiciently to actuate the mechanism and to prevent further discharge when the liquid has dropped to a predetermined level irrespective ofthe pressure increase.

With these and other objects in view, as` will be apparent to those skilled in the gart, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto. v

Referring to the drawing illustrating one embodiment of the invention, and in which like reference numerals indicate like parts, p

Fig. l is a vertical longitudinal section through a Valve mechanism;v`

Fig. 2 is an enlarged sectional View of the pilot valve shown in Fig. 1,"

Fig. 3 is an enlarged section on the line 3-3 of Fig. 2; and

Fig. 4 is an elevation showing the Valve mechanism connected to other apparatus.

The embodiment illustrated comprises a hollow valve body I0 divided internally by a U-shapedpartition lI into an inlet chamber I2 and an outlet chamber I4; The partition II is provided with two aligned ports I5 through which fluid may flow from the chamber I2 into the chamber I4 under the control of a vertically reciprocable seating-type main valve I6. This valve is biased upwardly toward its closed position by a coiled compression spring `I8 located beneath the valve and supported' by a cap I9 secured to the bottom of the body I0. This cap I9 is shaped to provide a guideway 2i) for a vertical stem 2| which extends downwardly from the valve I6.

A bonnet 23 is secured to the top of the body I i), this bonnet being shaped to provide a vertical cylinder 24 directly above the valve IS, with the lower end of the cylinder in communication with the outlet chamber I4. A piston 25 is slidably mounted in the cylinder 24 and.

connected to the valve I6 by a Vertical rod or stem 26. This piston provides a fluid-pressure actuated device which will, under certain conditions, open the valve I6 in opposition to the force of its biasing spring I8.

The iiuid pressure effective on the piston 25 is controlled Vby a pilot valve which in turn is actuated in accordance with variations in the level of a liquid. For this purpose the bonnet 23 is'divided internally by suitable partitionsv to provide an upper chamber 28, an intermediate chamber`29 and a lower chamber 3D. The upper chamber 28 is connected by a pipe 32 to the outletchamber I4 in the body I0, and the intermediate chamber 29 is connected by a passageway 33 in the bonnet 23'to the upper end of the cylinder 24. The lower chamber 3D Vcommunicates directly with theinterior of a hollow casing 34 which is secured to the bonnet 23 at one side thereof. This casing 34 has a screwthreaded opening 36 in its upper portion, and its lower portion is connected to the inlet chamber I2 in the body IIl by means of arpipe 3l provided with a manually adjustable needle'v'alve 38 which is partially open in the normal operation of the apparatus. Communication between the intermediate chamber 29 and the chambers 28`and 30 located respectively above and below the same is controlled by a suitable three-Way pilot valve mechanism.

The preferred construction for this pilot valve mechanism is shown in detail in Fig. 2 and comprises a cage 40, formed in two parts for convenience in assembly, and screw-threaded externally at 4I to facilitate its mounting within the bonnet 23. This cage is shaped to provide a central recess 42 from which ports 44 lead laterally to the intermediate chamber 29. In addition an outlet -port 45 leads upwardly from the recess 42 to the upper` chamber 28, and an inlet port 45 leads downwardly from the recess 42 to the lower chamber 3D. A vertically reciprocable pilot valve 48 is mounted within the recess 42, this valve having a stem 49 extending upwardly therefrom into the port 45 and a stem 50 eX- tending downwardly therefrom into the port 49. These valve stems are smaller in diameter than the ports and they are provided with radial ribs 5I which slidably engage the walls of the ports to guide the valve in its vertical travel. The lower valve stem 5D is surrounded by a small coiled compression spring 53 which engages a nut 54 on the lower end of this valve stem and i serves to urge the valve 48 downwardly.

The pilot valve 48 is controlled by means responsive to the level of liquid in the casing 34, and for this purpose I prefer to utilize a hollow spherical float 55 which is mounted on one end of a horizontal lever 55, this lever being fulcrumed, at its other end on a pin 5,1 supported by the bonnet 23. The lever 5S passes directly beneath the pilot valve, and the lower end of the pilot valve stem 55 rests against the upper surface of the lever near the fulcrum pin 5'I. These parts are so constructed and arranged that if the oat 55 moves upwardly the lever 56 will raise the pilot valve 48 and close the upper port 45,

whereas if the float moves downwardly the spring 53 will force the pilot valve downwardly until it closes the lower port 46.

The valve mechanism described labove is arranged to control the discharge of liquid refrigerant from one vessel to another. As. indicated in Fig. 4, the inlet chamber I2 in the valve body I is connected by a pipe 59 to a Vessel BD, and the outlet chamber I4l is connected by a pipe 6I to a second vessel 62. The opening 35 in the top of the casing 34 is connected by a pipe 63 to the rst vessel 69. The vessels 65 and 62 are two of a series of heat exchangers of known construction arranged to form ice by transferring heat from water to a refrigerant in liquid form.

The operation of the invention will now be described. During the freezing cycle in vessel 69 this vessel Will be filled with a suitable liquid refrigerant, such as ammonia, to a comparatively high level, the pressure being maintained at a predetermined pressure of say 39 pounds per square inch. Because of the high liquid level the float 55 will be held in its, raised position and the pilot valve 48 will likewise be raised, closing the upper port 45. The chamber 3U will be in communication with the upper end of the cylinder 24 through the port 45, recess 4 2, ports 44, chamber 29 and passageway 33. Thus the pressure in the vesselY D will be effective on the'top of the piston 2,5, but the main valve I6 will nevertheless be held closed by the forceI of the spring I 8.

When the freezing cycle in vessel 69 has been completed ammonia in gaseous form will be admitted to this vessel at a substantially higher pressure, and this pressure will be sufficient to farce.' the, Piston 2.5, downwardly and Open' the main valve I6 despite the force of the spring I8. Thus the liquid ammonia will be discharged from the vessel 60 through the pipes 59 and 6| to the vessel 62. V hen the liquid level in the rst vessel 60 has fallen sufliciently the float 55 will descend and the pilot valve 48 will be moved downwardly by the spring 53, opening the outlet port 45 and closing the inlet port 46. The outlet chamber I4 Will now be in communication with the upper end of the cylinder 24 through the pipe 32, chamber 28, port 45, recess 42, ports 44, chamber 29 and passageway 33. This will reduce the pressure above the piston 25, and the spring I8 will move the main valve I6 upwardly to its closed position. Upon-discharge of the ice from the vessel 60 this vessel will again be filled with liquid ammonia at substantially 30 pounds pressure, and the float will be raised once more to its original position. The needle valve 38 will remain in a partially open position to throttle the flow of the liquid through the pipe 3'I as the liquid level changes, thus preventing the float 55 from moving too suddenly.

It will now be apparent that the invention provides a valve mechanismof a simple and reliable construction adapted to control the flow of a liquid refrigerant in accordance with both the pressure and the level of the liquid. When the pressure increases sufciently the main valve will open, and when the liquid level drops sufficiently the main valve will close despite the increased pressure. f

Having thus described myY invention, what I claim as new and desire to secure by Letters Patent is:

l. In combination with a vessel arranged to be filled with liquid refrigerant at a predetermined pressure and having an outlet conduit, a valve to control the now in the conduit, a oat im mersed in the liquid anterior to the valve and movable vertically between an upper position `and a lower position in response to changes in the liquid level, means to maintain the valve in its closed position when the float is in its upper position and the refrigerant is at the said predetermined pressure, means to open the valve when the pressure of the refrigerant materially exceeds the said predetermined pressure and the float is in its upper position, and means to close the valve when the float is in its lower position irrespective of the pressure of the refrigerant.

2. In combination with a vessel arranged to be filled with liquid refrigerant at a predetermined pressure and having an outlet conduit, a valve to control the flow in the conduit, and biased toward its closed position, a float immersed in the liquid anterior to the valve and movable vertically between an upper position and a lower position iny response to changes in the liquid level, a fluid-pressure actuated device connected to the valve and arranged to open the valve in opposition to its bias when the device is subjected to a fluid-pressure materially exceeding the said predetermined pressure, means subjecting the device to the pressure` of the refrigerant anterior to the valve when the float is in its upper position, and means subjecting the device to the pressure of the refrigerant posterior to the valve when the float is in its lower position.

3. In combination with a vess'el arranged to be lled with liquid refrigerant at a predetermined pressure and having lan outlet conduit, a main valve to control the flow in the conduit, a fluidpressure responsive device connectedfto the valve to move the same toward open position, a pilot valve arranged to control the ilow of refrigerant to the device, means to actuate the pilot valve and admit refrigerant to the device when the liquid level is above a predetermined height, and means biasing the main valve toward its closed position with a force sufcient to hold it closed when the refrigerant in the vessel is at the said predetermined pressure and arranged to yield and allow the fluid-pressure responsive device to open the main valve when the pressure of the refrigerant on the said device materially exceeds the said predetermined pressure.

4. In combination with a vessel arranged to be filled with liquid refrigerant at a predetermined pressure and having an outlet conduit, a main valve to control the flow in the conduit, a uidpressure responsive device connected to the valve to move the same toward open position, a threeway pilot valve arranged to control the flow of refrigerant to and from the device, means to actuate the pilot valve and admit refrigerant to the device when the liquid level is above a predetermined height and to exhaust refrigerant Afrom the device when the liquid level is below the predetermined height, and means biasing the main valve toward its closed position with a force sufcient to hold it closed when the refrigerant in the vessel is at the said predetermined pressure and arranged to yield and allow the fluid-pressure responsive device to open the main valve when the pressure of the refrigerant on the said device materially exceeds the said predetermined pressure.

PAUL C. TEMPLE. 

